Transcriptomic analysis of the ΔPaLoc mutant of Clostridioides difficile and verification of its toxicity / 中华预防医学杂志

Objective: Comparative analyses of wild-type Clostridioides difficile 630 (Cd630) strain and pathogenicity locus (PaLoc) knockout mutant (ΔPaLoc) by using RNA-seq technology. Analysis of differential expression of Cd630 wild-type strain and ΔPaLoc mutant strain and measurement of its cellular virulence changes. Lay the foundation for the construction of an toxin-attenuated vaccine strain against Clostridioides difficile. Methods: Analysis of Cd630 and ΔPaLoc mutant strains using high-throughput sequencing (RNA-seq). Clustering differentially expressed genes and screening differentially expressed genes by DESeq software. Further analysis of differential genes using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Finally, cytotoxicity assays of ΔPaLoc and Cd630 strains were performed in the African monkey kidney epithelial cell (Vero) and the human colonic cell (Caco-2) lines. Results: The transcriptome data showed that the ΔPaLoc mutant toxin genes tcdA and tcdB were not transcribed. Compared to the wild-type strain, CD630_36010, CD630_020910,CD630_02080 and cel genes upregulated 17.92,11.40,8.93 and 7.55 fold, respectively. Whereas the hom2 (high serine dehydrogenase), the CD630_15810 (spore-forming protein), CD630_23230 (zinc-binding dehydrogenase) and CD630_23240 (galactitol 1-phosphate 5-dehydrogenase) genes were down-regulated by 0.06, 0.075, 0.133 and 0.183 fold, respectively. The GO and KEGG enrichment analyses showed that the differentially transcribed genes in ΔPaLoc were enriched in the density-sensing system, ABC transport system, two-component system, phosphotransferase (PTS) system, and sugar metabolism pathway, as well as vancomycin resistance-related pathways. Cytotoxicity assays showed that the ΔPaLoc mutant strain lost its virulence to Vero and Caco-2 cells compared to the wild-type Cd630 strain. Conclusion: Transcriptional sequencing analysis of the Cd630 and ΔPaLoc mutant strains showed that the toxin genes were not transcribed. Those other differential genes could provide a reference for further studies on the physiological and biochemical properties of the ΔPaLoc mutant strain. Cytotoxicity assays confirmed that the ΔPaLoc mutant lost virulence to Vero and Caco-2 cells, thus laying the foundation for constructing an toxin-attenuated vaccine strain against C. difficile.

Effect of Gastrodiae Rhizoma Powder on Prevention of Dementia and Oxidation Resistance in Mice / 中国实验方剂学杂志

Objective::To study whether long-term administration of Gastrodiae Rhizoma powder can improve the learning and memory ability of APPswe/PSldE9 double transgenic (APP/PS1) Alzheimer' s disease(AD) model mice and delay the progress of AD whether these effects are related to the regulation of antioxidant stress pathway in Kelch-like epoxylopropylamine-related protein 1(Keap1)-nuclear factor E2 related factor 2 (Nrf2)/heme oxygenase(HO)-1, and further explore the neuroprotective mechanism of Gastrodiae Rhizoma powder and its role in the prevention and treatment of AD. Method::APP/PS1 double transgenic mice model, the mice consisted of five groups: normal, normal administration group, model group, Gastrodiae Rhizoma powder prevention group, Gastrodiae Rhizoma powder treatment group.The mice in the normal administration group and the Gastrodiae Rhizoma powder prevention group were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) daily at the age of 8 weeks.The normal group and model group were given the same amount of normal saline at the same time, until 24 weeks old, Morris water maze was used to test the learning and memory ability of mice, and the treatment group was treated with Gastrodiae Rhizoma powder at 22 weeks old.The mice were given the same dose of Gastrodiae Rhizoma powder (1.5 g·kg-1) every day for 2 weeks.The number of crossing platform, escape latency and platform residence time of mice were detected by Morris water maze from 24 weeks old to 24 weeks old.RNA, Real-time PCR was extracted from mouse hippocampus to detect the mRNA level of Nrf2, HO-1, Keap1, and Western blot was used to detect the expression of Nrf2, HO-1, Keap1 protein in mouse hippocampus. Result::Compared with normal group, the water maze test showed that the learning and memory ability of model group was lower than that of the model group (P<0.01), and the learning and memory ability of Gastrodiae Rhizoma powder prevention group and Gastrodiae Rhizoma powder treatment group was significantly higher than that of model group (P<0.01). Compared with normal group, the levels of Nrf2, HO-1 and protein in the hippocampus in model group decreased in varying degrees (P<0.05). Compared with model group, Gastrodiae Rhizoma powder prevented Nrf2, in the hippocampus of mice in model group.The level of HO-1 in mRNA and protein increased in different degrees (P<0.05, P<0.01). Levels of Nrf2, HO-1 mRNA in Gastrodiae Rhizoma powder treatment group was significantly higher than that in Gastrodiae Rhizoma powder group (P<0.05). There was no significant difference in the expression of Nrf2, HO-1 protein.There was no significant difference in mRNA and protein levels of Keap1 among different groups. Conclusion::Morris water maze test and other results showed that Gastrodiae Rhizoma powder could improve the learning and memory ability of APP/PS1 mice, and it may enhance the expression of downstream antioxidant genes by regulating Keap1-Nrf2/HO-1 pathway.And then improve the learning and memory ability of APP/PS1 mice.

Effects of α3 neuronal nicotinic acetylcholine receptor on cell apoptosis and p38 MAPK signal transduction pathway in SH-SY5Y cells / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the effects of α3 neuronal nicotinic acetylcholine receptor (nAChR) on apoptosis and p38 signal transduction pathway in SH-SY5Y cells and to assess the roles of α3 nAChR in the pathogenesis of Alzheimer's disease (AD).</p><p><b>METHODS</b>The levels of α3 nAChR mRNA and protein were measured by real-time PCR and Western blot, respectively, in SH-SY5Y cells transfected with α3 nAChR siRNA. The mRNA level of bcl-2 and bax was measured by the real-time PCR. The siRNA transfected SH-SY5Y cells and control were then treated with 10 µmol/L Aβ25-35 for another 48 h, and the change in apoptotic rate and the levels of p-p38 and p38 were measured by flow cytometry and Western blot. Subsequently these SH-SY5Y cells were exposed to a blocker of p38 protein, and the apoptotic rate was measured again.</p><p><b>RESULTS</b>Compared to the controls, the expression of α3 nAChR at mRNA and protein levels in the SH-SY5Y cells transfected with α3 nAChR siRNA decreased by 95% and 86%, respectively; the mRNA levels of bax increased 2.11 times and that for bcl-2 decreased 0.53 times. The apoptotic rate was unaffected (3.40% ± 0.20%); but it increased after Aβ25-35 treatment (24.52% ± 1.59%); the level of p-p38 protein also increased by 178% in the α3 nAChR inhibited cells treated with Aβ25-35. Compared to controls, the Aβ25-35-treated SH-SY5Y cells and the Aβ25-35-treated and siRNA-transfected cells both showed a reduction in apoptosis after treatment with p38 blocker, especially in the former.</p><p><b>CONCLUSION</b>The siRNA silencing of α3 nAChR mRNA may enhance the effect of Aβ25-35 on the cell apoptosis by increasing the levels of p38 protein and bax mRNA and decreasing the level of bcl-2 mRNA, which may play a role in the pathogenesis of AD.</p>

Genetic association between interleukin-10 promoter microsatellite polymorphisms and hepatitis B virus infection in Yi, Yao and Han ethnic populations of Guizhou province / 中华流行病学杂志

Objective To investigate the association between interleukin-10 (IL-10) gene promoter microsatellite polymorphisms and the susceptibility to hepatitis B virus infection in Han,Yi and Yao ethnicities in GuiZhou province.Methods 500 volunteers were selected from Guizhou province.Ailelic frequency of IL-10.G and IL-10.R loci was identified by short tandom repeat polymerase chain reaction.The relativity between allelic frequency and HBV infection was analyzed.Results Genotype data from H-W analysis on all the IL-10 polymorphisms indicated that it was a random distribution.Very high HBV infection rates were found in the native ethnic minorities of Guizhou province.The overall HBV infection rate among the total population was 67.00％,with the HBV infection rates of Yi nationality in Weining,Yi nationality in Qianxi,Yao nationality in Libo and Han nationality in Libo as 51.85％,42.86％,79.52％ and 84.30％,respe~vely.The polymorphisms distribution of IL- 10.G and IL- 10.R were statistically different among the ethnic groups (P＜ 0.05 ).The polymorphisms distribution of IL-10.R had no significant difference between HBV infection group and non-infection group,as well as among HBV natural removal group and non-infected group in all the ethnic groups.The frequency of IL-10.G 459 bp (19CA) was significantly higher in non-infection group than in the infected group (P＜ 0.05 ).The frequency of IL-10.G 471 bp (25CA) was significantly higher in the non-infection group than in the HBV natural removal group(P＜0.05).The polymorphisms distribution of IL-10.G did not show significant difference between the HBV infection group and the HBV natural removal group in all the ethnic groups.We did not find any differences in allelic and genotypic frequencies of IL-10.G between infection group and non-infection group in Yi nationality in Weining,and Yao nationality in Libo (P＞0.05),as well as HBV natural removal group and non-infected group (P＞0.05).Conclusion The polymorphisms distribution of IL-10.R and IL-10.G did not show significant difference in Yi,Yao and Han ethnics population living in Guizhou province.IL-10.G seemed to influence the susceptibility of HBV infection in Han,Yao and Yi ethnics population of Guizhou province.

Influence of inhibited α7 nicotinic acetylcholine receptor gene expression on the production of β-amyloid peptide in SH-SY5Y cells / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the influence of inhibited α7 neuronal nicotinic acetylcholine receptor (nAChR) by small interference RNA (siRNA) in SH-SY5Y cells and to explore the connection of these changes with the β-amyloid precursor protein (APP) metabolism and the pathogenesis of Alzheimer's disease (AD).</p><p><b>METHODS</b>The siRNA of α7 nAChR was transfected into SH-SY5Y cells, and the expression of α7 nAChR and two subtypes of β-secretases (BACE1 and BACE2) at mRNA and protein levels was studied by real-time PCR and Western blot, respectively. The variation of Aβ(1-42) content was detected by ELISA.</p><p><b>RESULTS</b>As compared with controls, the expression of α7 nAChR at mRNA and protein levels in the SH-SY5Y cells transfected with the α7 nAChR siRNA were decreased by 84% and 79% (P < 0.01), respectively. The expressions of BACE1 mRNA and protein levels was increased by 527% and 71% (P < 0.01), respectively, while the expression of BACE2 decreased by 58% and 75% (P < 0.01), respectively. The Aβ(1-42) content increased by 208% (P < 0.01).</p><p><b>CONCLUSIONS</b>An inhibited α7 nAChR mRNA induced by siRNA may markedly stimulate the production of Aβ through the mechanism of increased expression of BACE1 and inhibited expression of BACE2, which may be related to the pathogenesis of AD.</p>

Influence of APP(SWE) transfection on nicotinic receptors in cultured neuronal cells / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the influence of APP(SWE) on the expression of neuronal acetylcholine receptors (nAChRs) and its relationship with Alzheimer's disease (AD).</p><p><b>METHODS</b>APP(SWE), carried the Swedish family AD double mutants, were transfected into SH-SY5Y cells and primary cultured neurons from rat brains to build a cellular model of AD. The mRNA levels of APP and nAChRs, and the protein levels of total APP, αAPPs and nAChRs in the cultured cells were measured using real-time PCR and Western blot, respectively. The numbers of α3 nAChR were determined by receptor-[³H]epibatidine binding assay.</p><p><b>RESULTS</b>Increased expressions of Swedish 670/671 APP at mRNA and protein levels, and down-regulation of αAPPs were observed in both of the cultured neuronal cells transfected with APP(SWE). A significant increase of α7 nAChR expression at protein and mRNA levels was detected in the APP(SWE) transfected SH-SY5Y cells. On the other hand, after transfection with APP(SWE), the expressions of α3 nAChR at protein and mRNA levels in SH-SY5Y cells, and α4 nAChR at mRNA level in primary cultured neurons were inhibited. In addition, the numbers of receptor binding sites were deceased in SH-SY5Y cells overexpressing with APP(SWE).</p><p><b>CONCLUSION</b>Overexpression of APP(SWE) can decrease αAPPs and modify nAChRs by increasing expression of α7 nAChR and decreasing α3 and α4 nAChRs, which might play an important role in the pathogenesis of AD.</p>

Blood routine test on the population in coal-burning fluoride toxicity in Bijie Country of Guizhou / 中国地方病学杂志

Objective To carry on a survey on blood routine examination of coal-burning endemic fluorosis population in Bijie City,Guizhou Province in order to study their health status and problems.Methods Blood routine examination was performed in the residents in coal-fired pollution endemic fluorosis-endemic area, including the residents of the Changchun Village of Changcun Town(intervention group)whose stoves had been improved and of Shiba Village Yachi Town not improved in Bijie City,Guizhou Province.The indicators were including leukocyte(WBC),red blood cell(RBC),hemoglobin(Hb),hematocrit(HCT),tlle average hematocrit red blood cell volume(MCV),mean corpuscular hemoglobin(MCH),mean corpuscular hemoglobin concentration (MCHC),red blood cell distribution width-CV(RDW-CV),platelets(PLT).Results RBC,Hb,HCT,MCHC, PLT were(4.95±1.18)×1012/L,(138.46±15.90)g/L,(50.19±11.48)%,(284.90±48.73)g/L,(334.92± 119.34)×109/L for the male in the intervened group,and they were(4.02±0.47)x 1012/L,(131.00±15.90)g/L, (40.90±7.60)%,(323.14±41.95)g/L,(280.79±100.34)× 109/L in non-intervention group,respectively. Inter-group comparison,the difference was statistically significant (U = 7.72,3.50,7.12,6.28,3.66,P ＜ 0.01). RBC, HCT,MCV,MCH,MCHC,RDW-CV,PLT were respectively(4.75±1.20)×1012/L,(46.91±11.20)%,(99.30± 6.88)fl,(28.10±8.66)pg,(275.61±54.49)g/L,(16.95±1.63)%,(351.23±150.37)×109/L for the female in the intervened group,and were (3.85±0.65)×1012/L,(38.80±6.60)%,(100.80±7.00)fl,(33.10±5.40)pg, (327.14±44.52 ) g/L,(16.60±1.58) %,(279.40±98.07)×109/L in the group un-intervened. Inter-group comparison found that there was a significant difference(U = 8.92,10.72,2.04,6.61,9.82,2.06,5.39,P ＜ 0.001 or 0.05) and the abnormal rate of RBC and Hb in non-intervention group[ 32.62% (92/282),16.67%(47/282)] was higher than that in the intervention group[9.73%(29/298) ,6.71%(20/298),x2 = 45.992,14.054,P ＜ 0.01 ) ]. Conclusion Experiment group has better results of blood routine test compared to non-intervention group,especially of anemia.

Neuroprotective effects of alpha7 neuronal acetylcholine receptor and its roles in the pathogenesis of Alzheimer's disease / 中华病理学杂志

<p><b>OBJECTIVES</b>To investigate the neuroprotective function of alpha7 nicotinic receptor (nAChR) and its roles in the pathogenesis of Alzheimer's disease (AD).</p><p><b>METHOD</b>Specific RNA interference to alpha7 nAChR mRNA expression was performed by gene specific small interference RNA (siRNA). SH-SY5Y cells were transfected with the siRNA or treated with 20 micromol/L 3-[2, 4-dimethoxybenzylidene] anabaseine (DMXB), an alpha7 nAChR agonist. After 48 hrs culture, levels of alpha7 nAChR mRNA and protein were monitored by RT-PCR and Western blotting, respectively. In the second experiment, SH-SYSY cells treated with siRNA or DMXB were exposed to 1 micromol/L Abeta(25-35), followed by protein analysis of alpha-form of secreted beta-amyloid precursor peptide (alphaAPPs), and total APP was assayed by Western blotting. In addition, lipid peroxidation and MTT [3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] reduction were measured by spectrophotometry.</p><p><b>RESULT</b>In RNA interference group, as compared with controls, alpha7 nAChR mRNA and protein levels were decreased with inhibitory efficiency by 80% and 69%, respectively, along with a decrease in protein levels of alphaAPP and reduction of MTT. However the product of lipid peroxidation was increased. There was an enhanced gene inhibition of alpha7 nAChR by Abeta. While cells treated with DMXB, the alpha7 nAChR protein was increased by 23% as compared with that of the control, along with decrease of alphaAPP and ERK 1/2 at the protein level. The enhanced expression of alpha7 nAChR reduced the neurotoxic effects resulted from Abeta.</p><p><b>CONCLUSION</b>The findings indicate that alpha7 nAChR may play a significant neuroprotective role by enhancing cleavage of APP, improving antioxidant defenses and limiting the toxicity of Abeta, which has been implied in the pathogenesis of AD.</p>

Influence of inhibited gene expression of alpha 3 nicotinic acetylcholine receptor by RNA interference on anti-oxidation in SH-SY5Y cells / 中华病理学杂志

<p><b>OBJECTIVES</b>To investigate the neuroprotective function of alpha 3 nicotinic acetylcholine receptor (nAChR) by inhibiting the gene expression in human neuroblastoma (SH-SY5Y) cells using small interference RNA (siRNA).</p><p><b>METHODS</b>The siRNA coding oligonucleotide sequences targeting alpha 3 nAChR were designed and synthesized. The annealed product was cloned into pSilencer 3.1-H1 neo vector. The recombinant alpha 3 nAChR pSilencer 3.1-H1 neo vector was transfected into the SH-SY5Y cells. The stable clones were screened by G418 medium, and the levels of alpha 3 nAChR mRNA and protein were monitored by using real-time PCR and Western blotting, respectively. After the SH-SY5Y cells with siRNA treatment were exposed to 1 micromol/L Abeta(1-42), MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide], SOD, GSH-px and the lipid peroxidation were measured by spectrophotometry.</p><p><b>RESULTS</b>Compared with the controls, the expression levels of mRNA and protein in the stable SH-SY5Y clone cells transfected with the recombinant alpha 3 nAChR pSilencer 3.1-H1 neo vector were decreased with inhibitory efficiency of 98% and 66%, respectively, the MTT reduction decreased; the product of lipid peroxidation was increased and the activities of SOD and GSH-px were decreased. Biologically, the gene expression inhibition of alpha 3 nAChR enhanced the toxicity induced by Abeta in SH-SY5Y cells.</p><p><b>CONCLUSIONS</b>The expression inhibition of alpha 3 nAChR as a result of recombinant alpha 3 nAChR siRNA can induce oxidative stress and improve the toxicity of Abeta on SH-SY5Y cells, indicating that alpha 3 nAChR may play a significant neuroprotective role in the pathogenesis of Alzheimer disease.</p>

Study on the association of IL-10-592 polymorphism with susceptibility to hepatitis B viral infection in Han, Yi and Yao ethnic groups in Guizhou province / 中华流行病学杂志

Objective To investigate the association of IL-10 gene promoter polymorphism with susceptibility to hepatitis B viral infection in Han, Yi and Yao ethnic groups from Guizhou province.Methods Five hundred volunteers from Guizhou province were selected to undertake PCR-RFLP for detection of IL-10 gene promoter -592 polymorphisim. Results The genotypic distributions of IL-10-592 were 32.53%- 51.43% (AA),40.74%-54.82% (AC),5.79%-18.52% (CC) whereas the allelic frequencies were 59.94% -72.38% for the A allele, and 27.62%-40.06% for the C allele in Han, Yi and Yao ethnics from Guizhou. The distributions of allele and genotype frequencies of IL-10-592 were statistically different between Yao ethnic in Libo and Yi ethnic in Qianxi, Yao ethnic in Libo and Han ethnic in Libo, Yi ethnic in Qianxi and Yi ethnic in Weining, Yi ethnic in Weining and Han ethnic in Libo (P ＜0.05). IL-10-592 polymorphism was associated with HBV infection in Yi ethnic in Qianxi and the whole population. Conclusion IL-10-592 gene polymorphisms influenced the susceptibility to HBV infection in Han, Yao, Yi sub-populations in Guizhou. Result of the study suggested that IL-10-592 gene polymorphisms might serve as a risk factor to HBV infection.

Influence of beta-amyloid protein and cholesterol on the pathological changes of Alzheimer's disease and expression of nicotinic acetylcholine receptors in rats / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the influence of beta-amyloid protein (Abeta) and cholesterol on the pathological changes of Alzheimer's disease (AD) and on the expression of nicotinic acetylcholine receptor (nAChR) subunits in the brains of rats.</p><p><b>METHOD</b>The rats were treated by intracerebroventricular injection of Abeta1-42 and fed with a diet containing 5% cholesterol to establish animal model of AD. The pathological changes, learning and memory, and expression of nAChRs of rats were analyzed by Bieoschowsky staining, immunohistochemistry, water-labyrinth, Western blot, and RT-PCR.</p><p><b>RESULTS</b>Abeta intracerebroventricular injection induced Abeta deposition in rat brains and high-cholesterol diet resulted in hypercholesterolemia in the animals. Injection of Abeta caused a reduction of learning and memory of rats and modifications of the expression of nAChRs. Cholesterol enhanced these effects of Abeta on neuropathology and expression of nAChRs.</p><p><b>CONCLUSIONS</b>Abeta can induce marked neuropathological changes, influence the learning and study ability, and modify the expression of nAChRs. Cholesterol can enhance the neurotoxicity of Abeta.</p>

Frequencies of GSTM1, GSTT1, and GSTP1 polymorphisms in ethnic minority from Guizhou / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the frequencies of GSTM1, GSTT1 and GSTP1 polymorphisms in Dong, Yi and Yao ethnic groups from Guizhou.</p><p><b>METHODS</b>In 321 volunteers who were population-based, GSTM1 and GSTT1 polymorphisms were analyzed by a multiplex-PCR procedure, whereas GSTP1 polymorphism was analyzed by PCR-RFLP method.</p><p><b>RESULTS</b>Null genotype for GSTM1 and GSTT1 was 59.6%-71.2% and 39.4%-72.5%, respectively. The genotypic distribution of GSTP1 was 63.3%-75% for AA, 23.2%-35.8% for AG, 0-1.9% for GG, whereas the allelic frequencies were 81.2%-86.6% for the A allele, and 13.4%-18.8% for the G allele.</p><p><b>CONCLUSION</b>There is a significant relationship between GSTT1 frequencies and ethnic populations.</p>

The genetic relation of four ethnic populations in China's Guizhou is revealed by sequence variations of mtDNA D-loop / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>Through maternal inheritance, to explore the genetic structures and relationships of Dong, Gelao, Tujia and Yi ethnic population in Guizhou of China.</p><p><b>METHODS</b>The mtDNA D-loop hypervariable segment I (HVS I ) in 108 samples of four ethnic populations were sequenced. Then, the nucleotide diversity was estimated and a phylogenetic tree was constructed by Neighbor-Joining method.</p><p><b>RESULTS</b>In the detected 497 bp fragments, 86 polymorphic sites were found, and 82 different haplotypes were identified. The phylogenetic tree of four ethnic populations showed: Yi, Tujia and Gelao clustered more closely than Dong did.</p><p><b>CONCLUSION</b>Yi and Tujia population are very closely related, the reason may be that they either originate from a common ancestry or frequently undergo the gene exchanges and admixtures. The genetic relationship between Tujia and Gelao population is nearer, perhaps because they have settled in the adjacent regions. Dong and Yi population show the farthest genetic relationship, this is probably due to their different historical origins and geographic segregation.</p>

Influence of beta-amyloid peptide on cell membrane lipids and cholinergic receptors in human neuroblastoma SH-SY5Y cells / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the effects of beta-amyloid peptide (Abeta) on cell membrane lipids and cholinergic receptors of human neuroblastoma cells.</p><p><b>METHODS</b>Human SH-SY5Y neuroblastoma cells were treated with different concentrations of Abeta(1-42) with and without pretreatment of vitamin E. MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] reduction, lipid peroxidation, protein oxidation and phospholipids were measured by spectrophotometry. Levels of cholesterol and unbiquinone were determined by high-performance liquid chromatography (HPLC). The numbers of cholinergic receptor binding sites were determined by receptor binding assay and the protein levels of nicotinic receptor alpha3 and alpha7 subunits were studied by Western blotting.</p><p><b>RESULTS</b>SH-SY5Y cells showed decreased reduction rates of MMT and phospholipids, and increased lipid peroxidation and protein oxidation after exposure to Abeta (0.1 micromol/L) as compared to the control. The number of cholinergic receptor binding sites, the protein level of nicotinic receptor alpha3 and alpha7 subunits and the content of ubiquinone decreased in cells treated with high dose of Abeta (1 micromol/L). Although the level of cholesterol was not changed in any way, vitamin E partially prevented the neurotoxic effects of Abeta.</p><p><b>CONCLUSION</b>beta-amyloid peptide reduces the level of cell membrane lipids and cholinergic receptors in human SH-SY5Y neuroblastoma cells, likely through the induction of an enhanced oxidative stress.</p>

G6PD Gene Mutations in Shui people in Sandu of Guizhou / 中国实验血液学杂志

<p><b>UNLABELLED</b>Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzymopathy. To date, about 126 mutations in the G6PD gene have been detected, among which 17 mutations were found in Chinese. The most common mutations are: 1376 G-->T and 1388 G-->A, both in exon 12; 95 A-->G in exon 2, which amounted to more than 50% of mutations representing various regions and ethnic groups in China. A large-scale screening and genotypic analysis was held in Shui people in Sandu of Guizhou. To investigate the incidence and the molecular basis of G6PD deficiency of Guizhou Shui people, NBT qualitative and G6PD/6PGD quantitative methods were used to detect G6PD deficiency in 1,090 Shui people from the general people belonging to Sandu of Guizhou. By means of mis-matched primers amplified the G6PD gene, the products were 234 bp, 280 bp and 345 bp in length, then restriction enzyme analysis was used to detect the most common Chinese G6PD mutations, 1376 G-->T, 1388 G-->A and 95 A-->G. The results showed that out of the 1,090 samples, 98 G6PD deficiency samples were found. The incidence of G6PD deficiency was 8.99%. 24 cases of 1376 G-->T, 12 cases of 1388 G-->A, 9 cases of 95 A-->G were detected. A sample with 1376 G-->T and 95 A-->G mutation was found in a girl. It was reported for the first time.</p><p><b>IN CONCLUSION</b>1376 G-->T, 1388 G-->A, 95 A-->G mutations are the common G6PD mutations in Shui people in Sandu of Guizhou. The results indicates that different national minorities of Chinese may originated from a common ancestor.</p>